A patient receiving a targeted therapy asks the nurse why St. John's wort must be avoided. Which response by the nurse is most appropriate?

Correct Answer: B

Rationale: St. John's wort induces the activity of cytochrome P450 enzymes, which metabolize many targeted therapies. This can lead to decreased blood levels of the targeted therapy, reducing its effectiveness. Patients should be advised to avoid St. John's wort to ensure optimal therapeutic outcomes. The other options are incorrect because St. John's wort does not increase blood levels of targeted therapies, cause overdose, or bind with drugs in the intestinal tract.

Correct Answer: A

Rationale: Thioridazine, a first-generation antipsychotic, potently blocks potassium channels, prolonging QT intervals and risking torsades de pointes, especially in patients with arrhythmias or on QT-prolonging drugs. This led to restricted use. Risperidone, asenapine, and lurasidone, second-generation agents, have milder QT effects. Aripiprazole is minimal. Thioridazine's strong association, evidenced by black box warnings, demands caution, making it the standout risk here.

Correct Answer: C

Rationale: Lithium is commonly used as a mood stabilizer in the treatment of bipolar disorder. It helps reduce the intensity of manic episodes, thereby stabilizing the patient's mood and preventing extreme mood swings. While lithium is primarily known for its mood-stabilizing effects, it is not used to lower blood glucose, slow the heart, or heal ulcers.

Correct Answer: A

Rationale: Angiotensin II receptor agents medications usually end in -sartan. Examples of such medications include losartan, valsartan, and telmisartan. These drugs work by blocking the action of angiotensin II at its receptor sites, resulting in vasodilation and decreased aldosterone secretion. This class of medications is commonly used to treat conditions like hypertension, heart failure, and diabetic nephropathy.

Correct Answer: D

Rationale: Infliximab, a biologic agent used to treat psoriasis, can suppress the immune system and increase the risk of infections and blood disorders. Monitoring the complete blood count (D) is a priority to detect neutropenia, anemia, or thrombocytopenia. Monitoring weight (A), electrolytes (B), or urine output (C) is not typically associated with infliximab therapy.